Usually involving catalase (from potato/liver) or amylase. You’ll likely investigate how or pH affects the rate of reaction. Pro tip: Always mention the "denaturation" of enzymes when explaining why a reaction stops at high temperatures. Osmosis and Diffusion
✅ I know how to write a and identify variables . ✅ I can describe food test procedures and results. ✅ I can use a microscope at low and high power. ✅ I can draw a biological specimen with labels. ✅ I can calculate percentage change in mass or length. ✅ I can interpret hydrogencarbonate indicator colours. ✅ I can explain why a control is needed. ✅ I can suggest modifications to improve accuracy (e.g., repeat, use larger sample, use a data logger). ✅ I can draw a line graph with labelled axes and a suitable scale. biology practicals o level
Can you translate what you see into a table or graph? 2. Common Practical Topics Usually involving catalase (from potato/liver) or amylase
| Nutrient | Reagent | Procedure | Positive Result | | :--- | :--- | :--- | :--- | | | Iodine Solution | Add a few drops to the sample. | Blue-Black (from orange-brown) | | Reducing Sugars | Benedict’s Solution | Mix sample with reagent. Heat in a water bath. | Green $\rightarrow$ Yellow $\rightarrow$ Orange $\rightarrow$ Brick Red precipitate | | Protein | Biuret Reagent | Add reagent to sample. Shake. Do not heat. | Purple / Violet (from blue) | | Fats (Lipids) | Ethanol & Water | Dissolve sample in ethanol. Pour into water. | Cloudy White Emulsion | Osmosis and Diffusion ✅ I know how to